Portable power-driven tool



Jan. 20, 1931. Hfwj osTER ET AL 1,789,412

PORTABLE POWER DRIVEN TOOL Filed Nov. 8, 1924 2 Sheets-Sheet 1 INVENTOR.

1 BY Qiezrnfl. 6742172 95 N a 20m r J/einzan ZJ. o-sicr 0/24 Jan. 20, 1931. H. w. OSTER HEAL 1,789,412

PORTABLE POWER DRIVER TOOL Filed Nov. 8, 1924 ZSheets-Sheet 2 INVENTORJ #6207742: 60. Oszez 412 y 6261212 .17. 15/66/72 ATTORNEYS Patented Jan. 20, 1931 unirso STATES arana? oFFicE HERMAN OSTERAN-D NN-names, QF CLEVELAND, HIQnssrenofi-s TomH osmaa MANUFACTURING COMPANY, or GLEVELAND,..OHIQ, A ,CORPORATIONrOE ,POBTABLE row-Barnum moot Application filed November.8, 1924. Serial No. 748,592.,

y available source of'power for driving 10-such a :tooland the design of the motor and of thedriving connections between such motor-and the the head proper presents a fur ther problem in that the-cutting speedof the diehead, asin any similar-machine-tool, is is determined by the peripheral speed in feet perni'inute. lnother words,Wherethethreadis being cut on a pipe or like article three inches indiameter, a slower speed in revolutions per minute is necessary than where threading a pipe one inch in'diameter. The li feand cutting qualities of the threading dies are ofcourse determined by the peripheral speed rather than by the actual revolutions penminute of the dies. It accordingly be- 25. comes necessary in the design of 'a portable threading tool of the type in question that the speed at which the die head is rotated be automatically controlled and this we obtain by means of the general characteristics of :the universal motor which we employ.

To the accomplishment of the foregoing and related ends the invention, then, consists of the means hereinafter fully described andparticularly pointed out in the claims, "the annexed drawings and the following description setting forth indetail certain'mechanism embodying-the invention, such disclosed mea-ns constituting, however,- but-one;

of various mechanical forms in -which the -princ'iple of the invention may be used,

In said annexed drawings: Fig; l is partly a central vertical section andpartlya side elevation of-one form of portable tool embodying our presentim- 4 z rovements; Fig. 2 is'a'bro'ken front-elevation-of-the same as viewed from the right in Fig. 1 and Figs. 3-to 8, inclusive,- are :broken SEOlOIlfizh-VIQWS'COIZGSPOIIdIIIg witha partwof Fig 'l but showing modifications in cons'truction.

Referring to the form -of-constru-ct-ion shown in Figs. 1 and '2, the frame of the mechanism willibe seen to'comprisetwo princ pal parts, namely, a motor-hous1ng il and a secondhousing 2 wherein 1s rotatably mountedatubular toolcarrying shaft- 31 The housing 1 is of general cylindrical shape to conform -with that of the motor encased therein, only-the-spindle 4' of the latter being show n'inFig, 1-. While an electric 'motor is thus desirably;e m-1: loye(l-and possesses special 'advan tages aswijll be presentlyxmore particularly explained, jit'w'ill be understood thatjso far as concerns the general assembly of the tool, --otl 1'er fOIIl'lSnOf power {than electricity may be employed, in which eventthe motor will be similarly disposed with respectto theotherparts of-the mechanism but will of course take on appropriate 'form and construction.-

The motor spindle lyit will'be noted; liestransverse'lyof'the axis of tubular Shaft 3 in casing 2 and is radially disposedwith respectto such axis. Keyedt'o thetubu lar shaft:

3 is an annular beveledgear 5 with which meshes a beveled pinion 6 that is keyed to the upperend-of a short shaft or spindle '17 aligned with motor spindle 4. Spindle 7 includes an intermediate enlarged portion 7a thatis journaked in a suitable bearing 8in the lower side wall'of casi-ng2, an additional bearing 9 being provided for the upper end-of said spindle ataipo'int closely adjacent to the tubular shaft 3, the pinion 6 being mounted on the spindle 7 between these two-bearings.- 'The enlargedrportion 7a of the spindle-projects beyond bearin-g 8 into a'supplemental casing 101of cylindrical form, to the lower open" end 1of-'-which is secured the upper end of the cylindrical motor housing 1. r

The driving connection between the motor spindle and said spindle 7 preferably takes the form of epicyclic reduction gearing of special design, such design by itself constituting no part of the present invention, although such gearing has been specially adapted for use herein. The driven member of such gearing is a spider 12 keyed on the enlarged portion 7a of spindle 7 such portion projecting sufiiciently for this purpose within the casing 10. Secured to the periphery of said spider and depending therefrom is an internal annular gear 13 with which mesh a plurality of pinions 14 freely rotatably mounted oncorrespon'ding spindles 1.5 that project upwardly from a carrier 16. The latter is stationarily secured to a centralboss 17 on the upper end of motor housing 1 through which extends the motor spindle 4. The portion 4a of motor spindle 4 that projects beyond the said boss 17 is of slightly reduced diameter and is journaled at its free end in a corresponding portion 16a of carrier 16, it being noted that the upper ends of the spindles 15, whereon are mounted pinions 14, are likewise supported in such carrier portion 16a. At an intermediate point such spindle extension 4a has keyed thereto a pinion 18 that meshes with a plurality of pinions 19. cor- -.responding with said pinions 14 and keyed to the hubs of the latter so as to be in effect integral therewith. .Pinions 19, however, are of larger diameter than pinions 14 and there is thus obtained a reduction in speed between the driving'member, consisting of pinion 18 on the motor spindle, and the driven member 12 on spindle 7 as will be readily understood.

The casing 2, in which tubular shaft 3 is journaled as aforesaid, is of flat cylindrical form, as indicated by its circular elevation as viewed from the front (see Fig. 2). The shaft 3 is formed with an encircling shoulder 20 that is held against a bearing ring 21, interposed between suchshoulder and one wall of the casing, a thrust ball bearing 22 being interposed between bevel gear 5 and the other wall of such casing. The latter is removable to. permit assembly of the parts and has fixed thereto a projecting shell 23 within which is slidably supported a second shell 23a that is splined thereto and has fixed to its outer end a work engaging device24. The latter is of thetype adapted non-rotatably to engage the work, i. e., it comprises a plurality of radially movable guides 246 that are adjustably positioned by a cam plate 24a, one of said guides having incorporated therein a threaded pin 240 that may be forced into firm engagement with the work.

Fixedly secured to the opposite end of the tubular shaft so as to be rotated thereby is a die stock or die head 25, likewise of standard construction, save that the oppositely extending handles are omitted. It is considered unnecessary for the purpose in hand to describe the details of construction of such head other than to note that it is provided with chaser dies 26 that may be suitably positioned in the head by appropriate adjusting means.

Instead of the adjustable work-engaging device of the type illustrated in Fig. 1, we may employ an interchangeable device as shown in Fig. 3, the same consisting of a ring 27 provided with radial arms 28 that slidably engage with pins 29 projecting from the adjacent face of housing 2 in a fashion similar to shell 23 in the first described construction. A set-screw 2'4'0 serves to secure the ring nonrotatably to the work when properly positioned on pins 29. There will-be a different ring for each diameter of work, one ring being slipped off and another on whenever change is necessary.

The electric motor employed to drive our improved tool is of the so-called universal type in that it is adapted to operate both on A. C. and D. C. current. An additional characteristic of this type of motor, which is of importance in the present connection, is that instead of operating at a constant speed, the speed thereof will automatically vary to suit the load. Thus, by way of illustration, in the case of a particular machine in which the motor is designed to produce a speed of 11 to 12 R. P. M. when threading a one inch pipe, the characteristics of the motor are such that when threading a three-fourths inch pipe, the speed automatically goes up to 16 R. P. M., while in threading pipe from onehalf to one-fourth inch in diameter, the speed of the motor will be approximately 20 R. P. M. If instead of such a universal motor having characteristics as stated, a constant speed motor of the type generally used on machine tools were employed, it will obviously be necessary to have, a number of change gears incorporated in the machine in order to attain these various speeds.

F or convenience in manipulating the tool, two oppositely disposed handles 30 are provided, as shown in Fig. 2, these being attached at their lower ends to casing 10 and at their upper ends to correspondin sides of casing 2. The electric current is carried to the motor through a line switch 31 operated by a lever 32 disposed adjacent the upper end of one such handle 30, areversing switch 33 being located adjacent the lower end of such handle with its lever 3a likewise disposed so that it may be manipulated by the hand which holds the handle in question.

It should be apparent that thetool need not be necessarily held to the work by means of the work engaging device of the type hereinbefore described. Thus, as shown in Fig. 4, the device in question may take the form of a simple work centering or guiding device such as is regularly found in a hand operated die stock. In adapting such device to the present construction, the end wall 35 of to the work other means may be provided as M12 housingfl is fo -med withan integraliegitens 0113 in Whi 'ehradial guide fi h re held;

these being ustably positioned means-oi a rotatabl amplate 3.

-: urthran difi= cation feature is rillus'tratedin Fig-41in that I thed-ie-head-39, corresponding with diehe'a'd plunger clears opening 41. Another die head may then be readily substituted with different dies 42, whetherof the chaser or other type.

In utilizing a tool of the construction shown in Fig. 4 and just described, the work will be held in a vise or the like with the end i to be threaded conveniently disposed so that the tool may be slipped thereon and properly centered by rotating cam 36a. The tool of course will require to be not only held tothe work, but also held against rotation by the operator, but this is not a heavy task where a thread of small diameter is being-cut.

here the tool is non-rotatably secured than the directly slidable work-engaging constructions shown in Figs. 1 and 3, respectively, whereby the die head may advance longitudinally of the work as is necessary in cidentally to the threading operation. Thus, in Fig. 5, a work engaging device 45 of the type shown in Fig. 1 is attached to a cylindrical shell 46 which is slidable within a second shell 47 that corresponds with tubular shaft 3, a spline 49 serving to lock the two shells against relative rotation but permitting longitudinal movement therebetween. The

i -die head '50 instead of being attached to shell 47, thus seen to correspond with tubular shaft 3, is directly attached to the face of housing 7 2. When thisform of tool is attached to the work by non-rotatably clamping device 45 t-hereto, rotation of beveled gear 5 will tend to rotate the work with respect to the die head, assuming that casing 2' is held against rotation as by grasping the handles provided for this purpose, inasmuch as said gear is ;keyed to shell 47 and the latter is in effect keyed to shell 46.

In Figs. 6 and 7, the modification consists in so attaching the die head that it'may slide l'ongitudinally'with respect tothe body of the tool. A work engaging device 51, again wh r by ratsvemevementbetween the-wen: andthe levi e :ipr vented, The die ahead 2 instea otb aghttabheql directly. to the forw r end-Qttubu a s aftjfiiFl; thaticorr spends it ,:-'sha f--3=in=- Eig. :1; :isattached tnthe. -:forward Kai(hot:v econd be 1 or? 53d 7 that is splined to said til-b91 52; so asflrto=be1non= rotatable relatively-to thegl-atter but freeyto mo eloag tu i ly hereof. I ltawill'he-noted that shelling Fig; 6) fits-i nterierly of, tubular shaft-.52, whileshe-ll ffitseXiterierlyj'of saidvtubularjshaft.

Finally in Ei-g .--.-8 ave show-still another I modification in; construct-ion which the tire hul sha 5 c rresponding with tubular; shaft 3 of the first'described:construction,;is

capable of sliding moveme nt relativelyto beveled; gear 5. :To this :end, said :shatt is pl i the gear, the groove aointhe shaft, wherewith the key '57 I engages, "being bf: suflffi= cient -l;en-gth to permit the desired ldngitudh nal movement of the shaft asrwillbe readijly understood, j The .work engaging; device v58, just asain thecase ofwor-li holding:device 1 n jig; -,*is e -a type whiohzis adaptedztobenon-retat-ably; clampedato-zthe work. i

The operational? the, th ree m illustrated in Figs. 6;, 7;,and8. similar in, at the, hous ng-2 nand thus the; tool, in t e main; is held against rotationwwith respect to the work by virtueot; the lockingengagement which the work engaging device: has with such =work.- 5 Movement of the die head- 25 inward-1y along. thawork-as the threading. ope-ration progresses incifclentallyto rotation of r the tubulanshell 52 or g 5-3, corresponding with tubular shaft- 3,will -accordingly be per ified forms? F tue oi thejnsp-lin'ed connection between shell 53 or shell 53a with ;sh;ell"5-2=..in the-ca'seyof Figs. 6 and; 7 andl byvirtue'ef' the directsplinefdengagement between, shell 55,-and 'the beveled gear-,5 in the casegof Fig; 8.

. Other modes of applying; the principle of our inventionmay' be employedrinstead of the one explained, change being :made, as regards the mechanism herei'n disclosed, Ip'ro vided the means "stated by anyzof the following claims .or-jt-hiezequivalent-of such stated means be employed. We -therefo-re particularly point out and distinctly. claimfas our invention 1. Ina portable power: fdr-ivenQtoo-l, the combination of a housing; a t-ubularsh'att rotatably-mounted ll'lfil fid extending through said housing; a tool carried; by 'oneiend, and

a work engaging device loy, the other end of saldshafi; an encircling shoulder. onwsaid v shaft adapted to prevent-'e-ndwis'e movement thereof with respect to one wall'ofsaid housing; abevel gear retatab'ly fixed on said sh'astt. between such shoulderand thenpposite wall of. said, honsing, said; gear facing: such first-v named wall; a thrust gbeari'ng interposed between the back of said gear and such second wall; a radially disposed spindle journaled in said housing; a bevel pinion fixed on said spindle and meshing with said gear a motor attached to said housing with its spindlein alignment with said first-named spindle; and reduction gearing interposed between said spindles.

2. A self-contained hand-portable device of the character described, which comprises a motor, a casing supported thereon, a tubular shaft rotatable in said casing, a die-holder mounted on one end of said shaft, workengaging means atthe other, an encircling shoulder on said shaft, a bevel gear on said shaft between such holder and the wall of said casing, a thrust-bearing back of said gear', a detachable cover plate for giving access to said bearing and gearing, a radiallydisposed spindle carrying a'pinion meshing with said gear, and driving connections between said motor and said spindle including reduction gearing. 1

3. In a power-driven portable threading machine, in combintaion, a main casing, a motor and a motor-driven trainof reduction gears, an auxiliary casing mounted on the end of the main casing, a sleeve rotatably mounted in the auxiliary easing, stocks and dies and apipe guide mounted on opposite ends of the sleeve, a bevelled ring gear fixed to the sleeve ata point between the pipe guide and stocks and dies, and a bevelled pinion gear actuated by said train of gears disposed to engage the ring gear when the auxiliary casing is in position on the main casing, the axis of the main casing extendng substantally at right angles to the axis of the sleeve, whereby the casing may be used as a lever for holding the machine during the operation of the stocks and dies.

l. In a portable threading machine in combination, a main casing, a motor an'd'motor driven train of gears, a'bevelled pinion gear driven by thetrain of gears, said pinion extending beyond the casing, an auxiliary casing on the main casing, a sleeve rotatably mounted in the auxiliary casing, a set of stocks and dies and a pipe guide mounted .on opposite ends of the sleeve and a bevelled ring gear fixed to the sleeve between the guide and dies, said ring gear being disposd to engage the pinion when the auxiliary casing is mounted in position on the main casing. V

5. In a portable threading machine in combination, a main casing, a motor and a motor-driven train of gears, a bevelled pinion gear driven by the train of gears, said pinion extending beyond the casing, an auxiliary casing on the main casing, a sleeve rotat'ablymounted in the auxiliary casing, a set of stocks and dies and a pipe guide mounted on opposite ends of the sleeve and a bevelled ring gear fixed to the sleeve between handlemeans inassociation with said main casing. a 1 Signed by us this 5th day of November,

HERMAN w. OSTER, GLENN n. SLE'ETH. 

